Carbondisulfide Derived Zwitterions

ABSTRACT

Amines and amine derivatives that improve the buffering range, and/or reduce the chelation and other negative interactions of the buffer and the system to be buffered. The reaction of amines or polyamines with various molecules to form polyamines with differing pKa&#39;s will extend the buffering range, derivatives that result in polyamines that have the same pKa yields a greater buffering capacity. Derivatives that result in zwitterionic buffers improve yield by allowing a greater range of stability.

BACKGROUND Field of the Invention

The present invention relates generally to the field of amines and moreparticularly to a classes of amino zwitterions.

Description of the Problem Solved by the Invention

Amines are extremely useful compounds in the buffering of biologicalsystems. Each class of amine has various limitations which requirechoosing an amine based on multiple factors to select the best amine.For example, pH buffering range is typically most important, but issuesof chelation, pH range stability, and solubility also come into play.Typically, a suboptimal buffer will result in yields that are well belowthe potential yield. The present invention improves the yields infermentation and purification, and improves shelf stability of proteinsand amino acids.

SUMMARY OF THE INVENTION

The present invention relates to amines and amine derivatives thatimprove the buffering range, and/or reduce the chelation and othernegative interactions of the buffer and the system to be buffered. Thereaction of amines or polyamines with various molecules to form aminederivatives and polyamines and derivatives with differing pKa's extendthe buffering range; derivatives that result in polyamines that have thesame pKa yield a greater buffering capacity. Derivatives that result inzwitterionic buffers improve yield by allowing a greater range ofstability and reduced conductivity.

DESCRIPTION OF THE FIGURES

Attention is now directed to the following figures that describeembodiments of the present invention:

FIG. 1-2 shows the synthesis of zwitterion type buffers fromnitroparaffins.

FIG. 3 shows the synthesis of dithicarbamates from a series ofbiolgically active amines.

FIG. 4 shows the synthesis of xanthates from nitroparaffins.

FIG. 5 shows the synthesis of derivatives of dithiocarbamates ofbiologically active amines.

FIG. 6 shows the synthesis of derivatives of aromatic dithiocarbamates.

FIG. 7 shows the synthesis of a range of derivatives based ondithiocarbmates of dopamine.

FIG. 8 shows the synthesis of dithiocarbamate dispersants and polyaminedithiocarbamate derivatives.

FIG. 9 shows dithiocarbamates from multifunctional secondary amines.

FIG. 10 shows the synthesis of pharmacologically interestingdiothiocarbamates.

FIG. 11 shows the synthesis of dithiocarbamates/xanthates hybrids andxanthates amino compounds from aminoalcohols and amino acid esters.

FIG. 12 shows the dithiocarbamates/xanthates based on the typical 3ethylene amines.

FIG. 13 shows the synthesis of benzyl functional zwitterionics.

FIG. 14 shows the synthesis of bis dithiocarbamates and bis xanthates

FIG. 15 shows the synthesis of a bis dithiocarbamate based on citricacid

FIG. 16 shows alkoxylates of dithiocarbamates

FIG. 17 shows the synthesis of alkoxylates of aminopyridines anddopamine as well as aminoalcohols.

FIG. 18 shows the synthesis of benzyl substituted amines

FIG. 19 shows the synthesis of bis-dithiocarbamates and amine oxides

FIG. 20 shows the N-sulfonic acids of a range of primarily secondaryamines.

FIGS. 21 and 22 show the synthesis of a range of therapeutic bioactivemolecules for treating diseases of the nuerosystem.

FIGS. 23 and 24 show the synthesis of a series of oil solublezwitterions and polyamines.

FIG. 25 shows the synthesis of a series of quaternary ammonium compoundswith a wide range of uses.

FIG. 26 shows the synthesis of surfactants useful as emulsifiers andother uses where hydrophilic and hydrophobic species need to come intoclose contact.

FIG. 27 shows the synthesis of ester amines, ester polyamines

FIG. 28 shows the synthesis of tertiary ester amine quaternaries.

FIG. 29 shows the synthesis of dithiocarbamates and dithiocarbamatehybrids from additional ethanolamines

FIG. 30 shows the synthesis of dithiocarbamates from ethylene amines

Several drawings and illustrations have been presented to aid inunderstanding the invention. The scope of the present invention is notlimited to what is shown in the figures.

DETAILED DESCRIPTION OF THE INVENTION

The reaction of carbon disulfide with nitroparaffins or nitroalcoholsform an intermediate from which xanthate and primary amine functionalitycan be present in the same molecule through relatively simple, and highyield reactions. FIGS. 1, 2 and 4 depict the route to nitro xanthates,which have utility as cross linking agents and vulcanizing agents andrubber. The nitro functionality improves adhesion of the rubber to thecord in steel belted radial tires and fiber reinforced tire applicationsas well as other reinforced rubber applications. The nitroxanthates canbe utilized as intermediates in the manufacture of primary aminefunctional xanthates for biological systems, agriculture andantimicrobials as well as many other applications. It should be notedthat here, as well as in other embodiments of the invention where areduction takes place when a xanthate or dithiocarbamate functionalityis present, the reduction of the nitro to the amine must be done underrelatively mild conditions to limit the co-products of reducing thexanthate functionality. The xanthates and dithiocarbamates haveadditional functionality in agriculture. The traditional uses such aschelants, and dispersants, are complimented by their use as antifungal,antimicrobial as well as growth regulators as promoters as well asphytocides and insecticides. Often the effects are more pronounced whenproduced as metal salts, such as zinc, tin, copper or any othertransition metal salts.

FIG. 3 shows the synthesis of dithiocarbamtes from a range ofbiologically interesting amines. The dithiocarbamates of the alaphaticand aminoalcohols are a low cost dispersant, cross linker, with uses inagricultural, antimicrobial, chelant, mining collector and buffer. Whilethe aromatic amine based dithiocarbamates are useful in the aboveapplications, the cost makes them less commercially viable in thoseapplications, however, they show great promise as therapies for diseasesof the nervous system, such as multiple sclerosis, Alzheimer's, andParkinson's diseases. The potential exists for these molecules and theirderivatives to be useful therapies as channel blockers as well, which isbelieved to be the mechanism by which the molecules of the presentinvention act as an MS therapy. Additionally, the dithiocarbamates areanti-oxidants and have potential as nutritional supplements as well ascancer therapies.

FIGS. 5, 6 and 7 show the synthesis of several classes of derivatives ofthe dithiocarbamates previously discussed. Several of the derivatives,particularly the pyridine containing derivatives, are biologicallyactive and potential therapies for mood disorders, multiple sclerosis,Alzheimer's disease, and Parkinson's disease. The carboxcylic acid andester containing derivatives primarily increase the dispersingcapability of the underlying dithiocarbamtes, reduce the chelating, orreduce the cost of manufacture. The molecules of FIGS. 6 and 7 thatcontain aromatic rings and require reduction, must be done under mildconditions, such as iron with turnings or under very mild conditionswith sponge metal catalysts at ambient temperatures and pressures ofless than 400 psi. The molecules of of FIG. 7 are typically simpleone-pot syntheses. FIG. 8 contains several dispersants that are moresurfactant in nature, with the higher carbon chain values of R beingfoam formers. The di-dithiocarbamates from diamines are strong chelantsthat are of the class bidentate, but tend to undergo ring closure if notkept under basic aqueous conditions. FIG. 9 further expands on thesebidentate chelants by introducing other chelant groups. Thus allowingfor a wider range of substrates for chelation and dispersion. FIG. 10shows a family of aminopyridine derived dithiocarbamates as well as adopamine diamine derived dithiocarbamates all of which arebiologically/pharmacologically interesting. Similar to those in FIGS. 6and 7, the reduction steps must be undertaken under mild conditions tominimize the reduction of the aromatic groups.

FIG. 11 shows the synthesis of dithiocarbamate/xanthates. Line i givesthe example of a dithiocarbamates that possesses an alcohol group.Further exposure to base and CS₂ will cause a xanthate to form in placeof the alcohol. Line ii carries this forward to include the single stepsynthesis where 1 or more alcohol groups are present. The A′, D′, and E′are where any alcohols, if present, have been converted to xanthategroups (—CH2OCS2H), if no alcohol is present for a specific A, D or E,then the prime of the original variable remains unchanged and theoriginal variable. It is understood by one of ordinary skill, that usingless than the full amount of CS₂ that can be reacted (or base/cation)will result in some alcohol groups not being converted to xanthategroups. This concept is shown in FIG. 12. These products are included aspart of the invention. This principle applies to lines iii through viias well. The same principle applies to the third line on FIG. 8. Ifalcohol groups are present, then they can be converted to xanthates asshown in FIG. 11. The addition of xanthate groups increases theefficiency of the molecule as a dispersant or mining collector, as wellas alter its solubility characteristics. Lines iii through vi producexanthates of amino acids or amino acid esters. The choice of J allowsfor a range of solubilities for the free molecule as well as the boundmolecule when acting as a chelant, collector or dispersant. Lines v andvi are the result of J being polyethyleneoxide in lines iii and iv. Itis understood that this is for illustrative purposes, and thatpolypropyleneoxide or polybutyleneoxide or other polyalkoxide is part ofthe invention, as well as their copolymers as J. Line vii shows anotherway of altering the solubility by substituting a less polar group as R.FIG. 12 shows the dithiocarbamates/xanthates based on the typical 3ethylene amines.

FIG. 13 shows the synthesis of benzyl functional zwitterions. Thereaction of the benzyl chloride species generates a free chloride ionthat will deactivate the amine to further reaction, so much harsherconditions or pH control are necessary to have the reaction go tocompletion. This becomes a problem once the reaction reaches half-way.In cases where there are hydroxyls present, the reaction will yield amix of products with some benzyl group addition occurring on the alcoholgroups as well as the amine. This is shown in the figure with a singlealcohol group present, but is not limited to a single addition. In thecases where more alcohol groups are present, the potential to add to anyof them exists leading to greater mix of reaction products. Enoughaddition of the benzyl chloride containing species can even form aquaternary amine group where two benzyl containing groups add at theamine group.

FIG. 14 shows the synthesis of bis-dithiocarbamates.Bis-dithiocarbamates are useful pharmacology, the most well knownbis-dithiocarbamate is disulfiram. FIG. 15 shows an expansion of thebis-dithiocarbmates by using citric acid as the starting material. FIG.16 shows the alkoxylation of the dithiocarbamates previously taught.While the Figure focuses primarily on the addition to the sulfur of thedithiocarbamates group, more aggressive reaction conditions andadditional alkoxylating agents will lead to a mixture of reactionproducts that include alkoxylation and polyalkoxylation at not just thesulfur, but at the secondary amine group, and any alcohols present. Inthe case where glycidol is used as an alkoxylating agent, condensationwith boric acid leads to particularly good corrosion inhibitors,anti-wear, and lubrication. The non-boric acid condensed products areuseful as anti-wear and lubrication additives in their right.

FIG. 17 shows the HLB balancing derivatives of buffers based onaminopyridines and dopamine. These adjustments will adjust thebioavailability of these buffers.

FIG. 18 shows the synthesis of n-benzyl functional amines. Amonosubstituted can be readily made to 50% yield, but pH control duringthe reaction (addition of base as the reaction proceeds to absorb thechloride ion produced) will allow the reaction to run to completion. N,Ndisubstituted amines can be made similarly. In the case where alcoholsare present in the A, D, or E group, the benzyl containing group willalso react on the alcohol group as shown in in the example. It isunderstood that additional alcohol groups are also subject tosubstitution if present and sufficient benzyl containing halide ispresent. Typically a mixture species with amine and alcohol substitutionwill be produced when alcohols and amines are present. The case of onealcohol and one amine, with 2 moles of the benzyl containing halide isshown with the dominant product.

FIG. 19 shows the synthesis of bis dithiocarbamates from diamines. Themono dithiocarbamates can be made from a diamine without introducingmineral salts, such as those of sodium or potassium. The methyl mono anddimethyl amines can also be made by reacting the primary amines withformaldehyde, followed by reduction, typically with hydrogen and spongenickel. FIG. 20 shows the N-sulfonic acids of secondary amines, as wellas the reaction of n-methyl compounds with monochloric acetic acid(MCA), sodium vinyl sulfonate (SVS), propane sultone. It is understoodthat higher sultones will react in an analogous fashion and areconsidered part of the invention. Alkoxylation of the n-methyl amines isalso taught. The polyoxyethylene derivatives may be mixtures, forexample the n-methyl amine may be ethoxylated, then propoxylated to forma block polymer chain off the nitrogen, these block and heteropolymerderivatives are within the scope of the invention. The synthesis ofpolyamines is taught via the reaction of acrylonitrile and the reductionwith hydrogen over sponge nickel. While the diamine is shown, a triamineand higher homologs can be synthesiszed through successive acrylonitrilereactions on the terminal amine group followed by reductions. Adding 1mole of acrylonitrile to a primary amine stepwise leads to linearpolyamines. Branching can be introduced by adding 2 moles ofacrylonitrile in any or all acrylonitrile additions. The polyamines,including the diamine, may be alkoxylated with any alkoxylating agent,typically ethylene oxide, propylene oxide, or butylene oxide in anycombination or amount will lead to polyoxyethylene derivatives of thepolyamines and are part of this invention, including the stepwise blockpolymerization with differing alkoxylating agents including therepeating of and alternating of various alkoxylating agents.

FIGS. 21 and 22 show the synthesis of a range of therapeuticaminopyridine derivatives and intermediates. The primary areas ofapplication are multiple sclerosis, Parkinson's, and Alzheimer's and asmonamine oxidase inhibitors. Antimicrobial effects are also observed inthe class.

FIGS. 23 and 24 show the synthesis of a range of derivatives of trialkylprimary amines. The largest source of which are the Dow Primene amines(from Dow Chemical). The dithiocarbamates are excellent miningcollectors for sulfide ores, such as nickel and copper in flotationrecovery as well as antimicrobial, dispersants and pest control. Severalzwitterionic species are shown that find utility in surface modificationof minerals in floatation mining and in personal care as cleaners. Thepolyamines are very useful anti-strips in asphalt emulsions. Thealkoxylates of both the Primenes and the polyamine derivatives makeexcellent power improvers in oil pipelines. The amine oxides areexcellent emollients and foam builders in personal care, especiallyshaving cream. While the drawings of the alkoxylation shows a secondaryamine resulting, anything over 1 mole of alkoxylating agent will resultin a tertiary amine with similar substitutions on both —H positions ofthe hydrogen. FIG. 25 shows the synthesis of quaternary ammoniumcompounds. The quaternaries are useful in oilfield as clay modifiers,converting clay, typically bentonite, into a hydrophobic clay fordrilling lubrication and for chip removal. The quaternaries are alsoexcellent corrosion inhibitors in oilfield pipelines. The trialkylquaternaries are excellent fabric softeners and anti-statics.Additionally, the quats and the dithiocarbamates are antimicrobial andare useful in agriculture for fungal and spore control, particularly theethylbenzyl quats and the dithiocarbamates. The quats are shown aschloride salts and as sulfate salts. This is for illustrative purposesonly, any other anion, such as acetate is part of the invention.

FIG. 26 further expands on the alkoxylation of the polyamines of FIG.24. The most commercially important of the group are the primary amines,which are used primarily as flotation and reverse flotation collectorsin iron ore or potash concentration processes. The use of the primaryamines of FIG. 24 can be used in the same manner as primary Tallowamine, Commonly known as Crisamine PT, by Crison Chemistry, orisodecyloxypropylamine, commonly known as Tomamine PA-14. The diaminesin FIG. 24 are useful as well and used similarly to tallow diamine,commonly known as Crisamine DT, andisodecyloxypropyl-1,3-diaminopropane, commonly known as Tomamine DA-14.The polyamines of FIGS. 24 and 26 are excellent anti-strips in emulsionasphalt formulations. The alkoxylates, are useful as emulsifiers toemulsify the bitumen in emulsion asphalt formulations. The most usefulof the alkoxylates are diamine with 3 moles of ethylene oxide, thetriamine with 4 moles of ethylene oxide, and the tertamine with 5 molesof ethylene oxide. Further, the partial or total neutralization withacetic acid of the primary amines, polyamines, and their alkoxylates aremore water soluble and improve their performance and particularly thehandling and application properties. FIG. 26 shows the acetate of theprimary amines, the acetates of the polyamines are made in the samefashion and are also part of the invention.

In the case of the asphalt emulsion formulations, the acetic acidevaporates, leaving a water resistant asphalt. The acetate of theprimary amine is helpful in mining as a collector in impartingsufficient water solubility for the collector to come in adequatecontact with the target mineral. Over neutralization leads to areduction in collector performance as the reduced hydrophobicity leadsto less flotation. A typical neutralization level of between 15 and 50%is most beneficial for the primary and diamines as used as collectors indirect ore flotation or reverse flotation processes. However anyneutralization level can be used.

FIG. 26 also shows the synthesis of amido acid surfactants. The amidoacid surfactants are also useful in mining to control hard water ionsthat interfere with the flotation process. In addition, the amido acidsurfactants can function as collectors as well. The amido acidsurfactants also make excellent surfactants for personal care productssuch as shampoo, lotions and facial scrubs where mildness is required.The amido acid surfactants also find utility in oil well drilling forcleaning out the formation and borehole walls.

FIG. 27 shows the synthesis of ester amines. The ester amines may bemonoalky, dialkyl, or trialkyl. To the extent that an alcohol group ispresent in the nitro alcohol, it may be esterified, so long as the nitrohas not been reduced to the amine. The reduction step needs to takeplace under milder conditions, where the temperature needs to becontrolled. Best results were seen where the temperature was kept below40 C. Poor results were seen when the temperature exceeded 120 C. Tooharsh conditions leads to breakdown of the ester linkage. FIG. 27 alsoshows the synthesis of polyamines, either through reacting acrylonitrilewith any remaining alcohol groups, or through the addition ofacrylonitrile to the amine. While the di and triamines are shown, higheranalogs can made through subsequent acrylonotrile additions andreductions. Branching can be introduced by adding 2 moles ofacrylonitrile per primary amine, or adding sufficient excess as to addto a secondary amine, then reducing the nitrile to the amine.Acrylonitrile based polyamines are typically most useful when reactedwith acrylo Useful asphalt emulsifiers can be made by alkoxylating orpolyalkoxylating the primary or secondary amine groups, similar to asshown in FIG. 26, as well as any of the alcohol groups. Most commonalkoxylating agents are ethylene oxide, propylene oxide, and butyleneoxide. However, any other alkoxylating agent may be used, and they areoften used in combination to add block copolymer structures to the amineor alcohol group. Further, anti-strips for hot and warm mix asphalt canbe made by making amides or polyamides by reacting the amine groups withfatty acid and driving off a mole of water per mole of fatty acid. Theester mono amines are useful as collectors in iron ore purification andpotash purification, as well as emulsifiers in asphalt to speed thesetting time. The dialkyl and trialkyl mono amines are useful asco-collectors.

FIG. 28 shows the synthesis of the analogous tertiary amines, as well astheir analogous methyl quaternaries. A wider range of quaternaries canalso be made by utilizing other quaternizing compounds as shown in FIG.25. Similarly, the methyl sulfate quats can be made by utilizingdimethyl sulfate instead of methyl chloride.

In the case of the derivatives that are produced as an ionic molecule,the pure zwitterion may be obtained through ion exchange as is routinelycarried out on an industrial scale. While the derivatives also show onlyone dithiocarbamate group, in many cases a second dithiocarbamate groupmay be obtained as disclosed in the earlier figures. The analogousdisubstituted derivative, or mono-substituted analogs are embodiments ofthe invention. Additionally, where ethylene oxide is shown as areactant, one skilled in alkoxylations will immediately recognize thatethylene oxide could be substituted with propylene oxide, butylene oxideor any other alkoxylate or any epoxide ring containg compound togenerate the analogous product. All of these analogs are within thescope of the present invention. For the derivatives where an amine groupresults, such as when acrylonitrile is reacted with the nitro xanthatesor dithiocarbamates, the amine group can further be derivatized withmonochloroacetic acid, allylic acids, sodium vinyl sulfonate, sultones,alkoxylated or phosphonated as shown in my previous patent applicationSer. No. 14/079,369. It is further understood by one skilled in the artthat higher sultones beyond propane sultone may be substituted andresult in the analogous product with additional carbon or carbonsbetween the sulfur and sulfonate group. All of these compounds are alsopart of the present invention.

FIG. 29 expands on FIG. 12 and shows that any amino alcohol can be madeinto a dithiocarbamate or dithiocarbamate/xanthate hybrid. FIG. 29simply expands this to explicitly include a wider range of ethanolaminesthat allows for greater control of selectivity as a mining collector,water solubility for mining depressants and dispersants. In the case ofaminopropyldiethanolamine, the dixanthate is shown, but the monoxanthatewhere a single hydroxyl is retained can be made by reacting with 2 molesof base and 2 moles of carbon disulfide.

FIG. 29 teaches the synthesis of very strong mining collectors fromethylene amines. FIG. 30 shows the synthesis of dithiocarbamates fromethylene amines. Amines groups can be retained in the final product byreducing the molar ratio of carbon disulfide and base. The innersecondary amine groups will be less reactive, and therefore the last toreact. The primary amine groups on the ends will be the first to react,and a mixture that contains the didithiocarbamate will also be presentwhen reacting more than 2 moles of carbon disulfide.

The xanthates and dithiocarbamates taught here are most stable and mosteasily made as salts. The salts are most commonly sodium salts due tothe cost effectiveness and availability of sodium hydroxide. While notshown as salts in the figures, it is understood that the salts arewithin the scope of the invention taught here. The free zwitterions orneutral forms are obtainable via ion exchange, and are what aretypically shown in the figures. This is shown explicitly in FIG. 9, inthe top reaction series. The salts are not generally shown in thefigures to make it clear that all salts, are included in the invention,not just sodium salts. Other bases can be utilized to drive theformation of the xanthates and dithiocarbamates. The resulting salts arewithin the scope of this invention. Of particular note are the use oftertiary amines to drive the xanthate or dithiocarbamate formation. Notonly are small, volatile tertiary amines useful, but so are fattytertiary amines, monoalkyl tertiary amines, such as the ADMA amines byLonza, di- and trialkyl tertiaryamines, including tertiary ether amines,such as those produced by Air Products, formerly Tomah Products. Alsouseful are the tertiary amines that result from alkoxylating primary andsecondary amines and ether amines, but care has to be taken not to causeaddition to the terminal hydroxyl group. This is controlled by addingthe alkoxylated amines in a way that there is a very slight excess ofcarbon disulfide at all times versus the alkoxylated amine and the amineto be converted to the dithiocarbamate. A further embodiment of theinvention taught is the use specifically of tertiary amines containingat least one alkyl branch that is from 10 to 14 carbons in making anydithiocarbamates or xanthates, not just the novel dithiocarbamates andxanthates presented here. These amines show antimicrobial activity thatcan be taken advantage of to produce dithiocarbamates complexes thathave synergistic levels of activity. In agriculture, the use of tertiaryamines as adjuvents is common. In particular, 15 moles of ethylene oxideor greater added to tallow amine, such as Akzo Nobel's Armeen T25, orthe ethoxylated ether amines, such as Tomamine E-17-5 producesdithiocarbamates that are more readily bioavailable to the targetorganisms. The use of such amines in the production of alldithiocarbamates and xanthates, not just the novel dithiocarbamates andxanthates taught here, produces dithiocarbamates and xanthate complexesthat are much more effective and all such complexes are within the scopeof the present invention.

The mineral bases such as lime, calcium hydroxide or potassium hydroxideand all others enable the production of the molecules taught, butwithout sodium. This is particularly important in agriculturalapplications. The agricultural applications also benefit from the fattytertiary amines in that they help the dithiocarbamates or xanthatespenetrate the target organism that is to be controlled. If desired, thedithiocarbamates can be made with the starting amine as the counter ion.In this case, two molar equivalents of the amine needs to be utilized toone molar equivalent of carbon disulfide during manufacture.

While much of the benefits of these molecules have been recognized inbiological systems, the zwitterions and derivatives are also known to bebeneficial as dispersants, chelants, cross-linkers, antimicrobials,preservatives of organic systems, and pH buffers in oilfield drillingsystems and hydraulic fracturing. Additionally, the molecules of thepresent invention find utility as collectors in mining and asdepressants. Further, in ball milling, the dispersant characteristicsimprove the characteristics of ore pellets. The zwitterionic moleculesof the present invention also find utility in high energy storagesystems, such as lithium ion and lithium polymer batteries as a means ofimproving charge transport and as acting as a salt bridge in otherbattery applications. These compounds also find application as asphaltantistrip.

Several descriptions and illustrations have been presented to enhanceunderstanding of the present invention. One skilled in the art will knowthat numerous changes and variations are possible without departing fromthe spirit of the invention. Each of these changes and variations arewithin the scope of the present invention.

I claim:
 1. The mining collector and its amine and metal salts of thefollowing structure:

wherein A is —CH3 or —CH2CH2OR, and is R is —H or —CS2H.
 2. The miningcollector and its amine and metal salts of claim 1 wherein A is —CH3. 3.The mining collector and its amine and metal salts of claim 1 wherein Ais CH2CH2OR and R is —H or CS2H.
 4. The mining collector and its amineand metal salts of claim 3 wherein R is —CS2H.
 5. The mining collectorand its amine and metal salts of claim 3 wherein R is —H.
 6. The miningCollector and its amine and metal salts of the following structure:

wherein is R is —H or —CS2H; A is —CH3 or —CH2CH3.
 7. The miningCollector and its amine and metal salts of claim 6 wherein A is —CH3 andR is —H or —CS2H.
 8. The mining Collector and its amine and metal saltsof claim 7 wherein R is —H.
 9. The mining Collector and its amine andmetal salts of claim 7 wherein R is —CS2H.
 10. The mining Collector andits amine and metal salts of claim 6 wherein A is —CH2CH3 and R is —H or—CS2H.
 11. The mining Collector and its amine and metal salts of claim10 wherein R is —H.
 12. The mining Collector and its amine and metalsalts of claim 10 wherein R is —CS2H.
 13. The mining collector and itsamine and metal salts of the following structure:

wherein is R and R′ are independently chosen from —H or —CS2H, n is anon-negative integer.
 14. The mining collector and its amine and metalsalts of the following structure:

wherein is R and R′ are independently chosen from —H or —CS2H.